The invention discloses a hybridoma cell strain with a preservation number of CGMCC NO.11182, a monoclonal antibody obtained through secretion of the cell strain, and the application thereof. The invention further provides an immunoadsorbent, wherein the immunoadsorbent comprises a solid phase carrier and antibodies coupled with the solid phase carrier, and the antibodies include the monoclonal antibody and a chloramphenicol-resisting antibody. The invention also provides an immunoaffinity column loaded with the immunoadsorbent. The invention further provides a kit containing the immunoadsorbent or the immunoaffinity column, the application of the immunoadsorbent, the immunoaffinity column or the kit to purification and/or detection of olaquindox and chloramphenicol, and a purification method and a detection method. By using the products and methods, olaquindox and chloramphenicol can be purified and/or detected at the same time.